A person's movements may be used to control electronic devices. A hand movement or movement of another part of the person's body can be detected by an electronic device and used to determine a command to be executed by the device (e.g., provided to an interface being executed by the device) or to be output to an external device. Such movements by a person may be referred to as a gesture. Gestures may not require the person to physically manipulate an input device. Rather, one or more images of the person may be captured to identify the gesture being performed. As an example, when watching television, a person may use gestures to change the channel, raise and lower the volume, and/or shut off the television. A hand or some other part of a person's body may be used to perform each gesture. Similarly, an object held or controlled by the person may be used to perform the gesture.
Gestures may be useful to control devices. However, reliably detecting gestures, or, more generally, determining a position of a part of a person's body, may be difficult and/or computationally expensive.